Blower filter device for potentially explosive areas and process for operating a blower filter device

Abstract

A blower filter device ( 3 ) is connectable to a voltage supply unit ( 2 ) and includes a blower unit ( 5 ), a filter mount ( 14 ), an internal energy storage unit ( 7 ), an energy interface ( 9 ), a current limitation device ( 13 ), a sensor array ( 16, 17, 18 ) and a control device ( 6 ). The current limitation device is activated upon disconnecting the energy interface from the voltage supply unit. The activated current limitation device limits the intensity of a current from the energy interface to the internal energy storage device. Upon the voltage supply unit being connected to the energy storage device and a predefined deactivating event is detected, the control device deactivates the current limitation device. The deactivating event is based on a charging voltage of the internal energy storage unit and/or on a time period that has elapsed since the connection. A process is provided for operating such a blower filter device.

The invention claimed is: 
     
       1. A blower filter device comprising:
 a blower unit for generating an air stream; 
 a filter mount for accommodating a filter unit; 
 an internal energy storage unit; 
 an energy interface, wherein the internal energy storage unit is connected electrically to both the blower unit and the energy interface and is chargeable with electrical energy and is configured to release the electrical energy, and wherein the energy interface is configured to be electrically connectable to a voltage supply unit and to be electrically disconnectable from the voltage supply unit; 
 an activatable and deactivatable current limitation device; 
 a sensor array; and 
 a control device, 
 wherein the blower filter device is configured such that the current limitation device is activated when the energy interface is disconnected from the voltage supply unit, 
 wherein the activated current limitation device is configured to maintain an intensity of a current from the energy interface to the internal energy storage unit below a predefined current intensity limit, 
 wherein the sensor array is configured to detect a predefined deactivating event, wherein the deactivating event has occurred:
 if a state of charge of the internal energy storage unit has exceeded a predefined state of charge limit and/or 
 if a predefined time period has elapsed since the establishment of an electrical connection between the energy interface and the voltage supply unit, and 
 
 wherein the control device is configured to deactivate the current limitation device after the detection of the deactivating event such that the internal energy storage unit is connected electrically to the energy interface after the deactivation without limitation to the predefined current intensity limit. 
 
     
     
       2. A blower filter device in accordance with  claim 1 , wherein the sensor array comprises a voltage sensor configured to measure a variable, which is correlated with an electrical output voltage or a charging voltage of the internal energy storage unit. 
     
     
       3. A blower filter device in accordance with  claim 1 , wherein the sensor array comprises:
 a connection sensor; and 
 a time period sensor, 
 wherein the connection sensor is configured to detect that the voltage supply unit is connected electrically to the energy interface, and 
 wherein the time period sensor is configured:
 to measure a time that has elapsed since establishing the electrical connection between the energy interface and the voltage supply unit, and 
 to compare the elapsed time with a predefined threshold value. 
 
 
     
     
       4. A blower filter device in accordance with  claim 1 , wherein the current limitation device comprises:
 a current limitation unit; and 
 a switchable electrical connection unit, 
 wherein the connection unit is arranged in parallel to the current limitation unit, and 
 wherein the switchable electrical connection unit connects the energy interface electrically to the internal energy storage unit in a conduction state and interrupts this connection in a blocked state, and 
 wherein the control device is configured to switch the electrical connection unit from the blocked state into the conduction state after the detection of the deactivating event. 
 
     
     
       5. A blower filter device in accordance with  claim 4 , wherein the switchable electrical connection unit has a bidirectional thyristor diode and/or a bidirectional diode and/or a transistor and/or a relay and/or a mechanical contact and/or a spark gap. 
     
     
       6. A blower filter device in accordance with  claim 1 ,
 wherein the current limitation device has at least one electronic component with a variable electrical resistance value, and 
 wherein the control device is configured to reduce the electrical resistance value of this component after the detection of the deactivating event. 
 
     
     
       7. A blower filter device in accordance with  claim 6 , wherein the electronic component comprises at least one transistor and/or a potentiometer. 
     
     
       8. A blower filter device in accordance with  claim 7 , wherein the control device is configured to reduce the electrical resistance value as a function of the state of charge of the internal energy storage unit. 
     
     
       9. A blower filter device in accordance with  claim 7 ,
 wherein the electronic component comprises at least one transistor, which can partially or fully be biased into conduction, and 
 wherein the electrical resistance value of the transistor biased partially into the conduction is higher than that of the transistor biased fully into the conduction. 
 
     
     
       10. A blower filter device in accordance with  claim 1 , wherein the control device is configured to automatically activate the current limitation device in response to the disconnection of the energy interface from the voltage supply unit. 
     
     
       11. A blower filter device in accordance with  claim 1 , wherein the blower unit can be switched on and can be switched off, and the blower filter device is configured to automatically activate the current limitation device in response to the switching on and/or switching off of the blower unit. 
     
     
       12. A blower filter device in accordance with  claim 11 ,
 wherein the blower filter device comprises an actuating element for switching on and switching off the blower unit, and 
 wherein the actuating element is connected to an electrical connection between the current limitation device and the energy interface such that an actuation of the actuating element for switching on the blower unit connects the current limitation device electrically to the energy interface and an actuation of the actuating element for switching off the blower unit disconnects the current limitation device electrically from the energy interface. 
 
     
     
       13. A blower filter device in accordance with  claim 1 ,
 wherein the blower filter device comprises a storage unit for accommodating the voltage supply unit, and 
 wherein the storage unit is configured such that the voltage supply unit accommodated by the storage unit is connected electrically detachably to the energy interface. 
 
     
     
       14. A blower filter system comprising:
 a voltage supply unit; and 
 a blower filter device comprising: 
 a blower unit for generating an air stream; 
 a filter mount for accommodating a filter unit; 
 an internal energy storage unit; 
 an energy interface, wherein the internal energy storage unit is connected electrically to both the blower unit and the energy interface and is chargeable with electrical energy and is configured to release the electrical energy, and wherein the energy interface is configured to be electrically connectable to the voltage supply unit and to be electrically disconnectable from the voltage supply unit; 
 an activatable and deactivatable current limitation device; 
 a sensor array; and 
 a control device, 
 wherein the blower filter device is configured such that the current limitation device is activated when the energy interface is disconnected from the voltage supply unit, 
 wherein the activated current limitation device is configured to maintain an intensity of a current from the energy interface to the internal energy storage unit below a predefined current intensity limit, 
 wherein the sensor array is configured to detect a predefined deactivating event, wherein the deactivating event has occurred:
 if a state of charge of the internal energy storage unit has exceeded a predefined state of charge limit; and/or 
 if a predefined time period has elapsed since the establishment of an electrical connection between the energy interface and the voltage supply unit; and 
 
 wherein the control device is configured to deactivate the current limitation device after the detection of the deactivating event such that the internal energy storage unit is connected electrically to the energy interface after the deactivation without limitation to the predefined current intensity limit. 
 
     
     
       15. A breathing air supply system comprising:
 a blower filter device comprising: 
 a blower unit for generating an air stream; 
 a filter mount for accommodating a filter unit; 
 an internal energy storage unit; 
 an energy interface, wherein the internal energy storage unit is connected electrically to both the blower unit and the energy interface and is chargeable with electrical energy and is configured to release the electrical energy, and wherein the energy interface is configured to be electrically connectable to a voltage supply unit and to be electrically disconnectable from the voltage supply unit; 
 an activatable and deactivatable current limitation device; 
 a sensor array; and 
 a control device, 
 wherein the blower filter device is configured such that the current limitation device is activated when the energy interface is disconnected from the voltage supply unit, 
 wherein the activated current limitation device is configured to maintain an intensity of a current from the energy interface to the internal energy storage unit below a predefined current intensity limit, 
 wherein the sensor array is configured to detect a predefined deactivating event, wherein the deactivating event has occurred:
 if a state of charge of the internal energy storage unit has exceeded a predefined state of charge limit; and/or 
 if a predefined time period has elapsed since the establishment of an electrical connection between the energy interface and the voltage supply unit; and 
 
 wherein the control device is configured to deactivate the current limitation device after the detection of the deactivating event such that the internal energy storage unit is connected electrically to the energy interface after the deactivation without limitation to the predefined current intensity limit; 
 a face mask; and 
 a connection unit configured to establish a fluid connection between the blower filter device and the face mask. 
 
     
     
       16. A process for operating a blower filter device, wherein the blower filter device comprises a blower unit for generating an air stream, a filter mount for accommodating a filter unit, an internal energy storage unit and an energy interface, wherein the internal energy storage unit is connected electrically to the energy interface, the process comprising the steps of:
 electrically connecting the energy interface to a voltage supply unit at least once; 
 providing the blower filter device so that the blower filter device further comprises a current limitation device, a control device and a sensor array, activating the current limitation device before the step of electrically connecting; wherein the following steps are carried out after the connection: 
 maintaining, with the activated current limitation device, an intensity of a current from the energy interface to the internal energy storage unit below a predefined current intensity limit; 
 detecting, with the sensor array, a predefined deactivating event, wherein the deactivating event will have occurred when the state of charge of the internal energy storage unit has exceeded a predefined state of charge limit and/or when a predefined time period has elapsed since the establishment of an electrical connection between the energy interface and the voltage supply unit; and 
 deactivating, with the control device, the current limitation device after the detection of the deactivating event such that the intensity of the current from the energy interface to the internal energy storage unit is not limited to the predefined current intensity limit after the detection of the deactivating event. 
 
     
     
       17. A process in accordance with  claim 16 , wherein the blower filter device comprises a storage unit for accommodating the voltage supply unit, and the step of connecting the energy interface electrically to the voltage supply unit is carried out with the voltage supply unit and it comprises the step of inserting the voltage supply unit into the storage unit such that the voltage supply unit is electrically connected to the energy interface after the insertion. 
     
     
       18. A process in accordance with  claim 16 , wherein at least one of the steps of
 connecting the energy interface to the voltage supply unit or 
 disconnecting the energy interface from the voltage supply unit is detected automatically and the at least one of the steps triggers the step of the control device automatically activating the current limitation device. 
 
     
     
       19. A process in accordance with  claim 16 ,
 wherein the blower unit can be switched on and switched off repeatedly, 
 wherein the current limitation device is activated with the blower unit switched off, 
 wherein the step of switching off the blower unit triggers the step in which the control device activates the current limitation device, and 
 wherein the step of switching on the blower unit triggers the step in which the control device deactivates the current limitation device after the detection of the deactivating event.